Engine lubricating system



Jan. 5, 1960 A. RODER ENGINE LUBRICATING SYSTEM Filed Nov, 26, 1956 United States Patent ENGINE LUBRICATIN G SYSTEM Albert Roder, Heilbronn, Germany, assignor to NSU Werke A.G., Neckarsulm, Wurttemberg, Germany Application November 26, 1956, Serial No. 624,367 Claims priority, application Germany December 2, 1955 3 Claims. (Cl. 184-6) This invention relates to a camshaft drive for an internal combustion engine with an overhead camshaft, in which the positive connection from the crankshaft is effected by way of a crown wheel and from the latter by means of connecting rods and eccentrics. Owing to their quietness, such eccentric drives for overhead camshafts have in recent times been very successfully introduced in vehicle motors, particularly in single-cylinder motor cycle motors. For this reason attempts are also being made to introduce this drive in multi-cylinder internal combustion engines. The invention concerns an advantageous construction of such a connecting rod drive, in which a short eccentric shaft, situated more or less coaxially with the camshaft, is mounted in a rocker.

Compared with what is known in the art, the invention provides a drive of the camshaft by the eccentric shaft which is free from play and simple to manufacture, and also provides the means of supplying the lubricant to the eccentric bearings. According to a further feature of the invention the bridging-over point of the oil flow is constructed as an excess pressure balancing means.

One embodiment of the camshaft drive according to the invention is illustrated in the drawings, in which:

Figure 1 shows a part of one cylinder head of the internal combustion engine in plan, the camshaft and eccentric bearings being in horizontal section.

Figures 2 and 3 show the connecting point between eccentric shaft and camshaft, with Fig. 3 being a section taken along the line AB of Fig. 2, the view looking in the direction of the arrows and,

Figure 4 is a perspective representation of the cylinder head section according to Figure 1.

Referring to the drawings, it will be seen that a camshaft 1 is mounted within cylinder head 2 and eccentric shaft 3 is associated therewith. A rocker unit 4 for the shaft 3 is provided and a spacer is denoted 5 with 13 indicating connecting rods.

The shaft 1 is provided with a longitudinally extending channel 6 for the lubricant and cams 7 are carried by the camshaft 1. The connection through which the lubricant passes between the shafts 1 and 3 is centrally arranged and the lubricant in the channel 6 is led by way of bores 14 and 15 to the individual lubricating points. The shafts 1 and 3 are connected by a connecting member 8, which as can be seen from Figs. 2 and 3 is eccentrically located or in other words is outside the oil supply components. The member 8 is positively connected to the eccentric shaft 3 by means of a pin 10 and to the camshaft by a pin 9.

The connection through which the lubricant passes or the oil-tight juncture between the shafts 1 and 3 is accomplished by a centrally located spring-loaded box or sleeve 11 (Fig. 1) which is resiliently urged by spring means 12 against front face of the shaft 3. On the other side, the box 11 projects into a widened bore 14A and thereby defines the sealing means.

7 2,919,768 Patented Jan. 5, 1960 The spring loaded box is introduced into the bore 14A and the excess oil can escape between the flange of the box or sleeve and the face of the shaft 3. However, this occurs only when oil accumulates and is under a certain amount of pressure, and then the box is forced into the bore 14A in a direction opposite to that of the spring pressure.

The widened bore 14A is so selected that the box 11 can be retracted at a certain oil pressure. The escaping lubricant oil then flows to a collecting chamber not illustrated in the drawings.

The invention is not to be confined to any strict conformity with any showing in the drawings but changes and modifications can be made therein so long as such changes and modifications mark no material departure from the spirit and scope of the appended claims.

I claim:

1. In a crankshaft drive for an internal combustion engine, a cylinder head, an overhead cam shaft fixedly mounted in the cylinder head, a rocker mounted in the cylinder head, an eccentric shaft arranged in the rocker with the said shafts being in axial alignment and with the adjacent ends of said shafts being spaced apart, connecting rods operably connected to the eccentric shaft to drive the same, the cam shaft and the eccentric shaft having channel means therein for supplying oil for the cam shaft bearing, the cams and the eccentric bearing, a centrally located conduit means between the cam shaft and the eccentric shaft connecting said channel means and providing an oil-tight juncture between the shafts, a connecting member positioned between the adjacent ends of the shafts eccentrically located with respect to the centrally located conduit means, and pin means extending between said cam shaft and connecting member, and between said connecting member and eccentric shaft for operably connecting said shafts.

2. In a crankshaft drive for an internal combustion engine, a cylinder head, an overhead cam shaft fixedly mounted in the cylinder head, a rocker mounted in the cylinder head, an eccentric shaft arranged in the rocker with said shafts being in axial alignment and with the adjacent ends of said shafts being spaced apart, connecting rods operably connected to the eccentric shaft to drive the same, the cam shaft and eccentric shaft having channel means therein for supplying oil for the cam shaft bearing, the cams and the eccentric bearing, and a centrally located conduit means between the cam shaft and the eccentric shaft connecting said channel means and providing an oil-tight juncture between the shafts, said centrally located conduit means including an axially spring loaded sleeve operatively associated with one of said shafts and resiliently urged against the opposing face of the other shaft.

3. A crankshaft drive as claimed in claim 2 in which the face of the shaft with which the sleeve is operatively associated is provided with a bore of such diameter that when the desired maximum oil pressure in the engine circuit is exceeded, the sleeve is retracted into the bore.

References Cited in the file of this patent UNITED STATES PATENTS 1,264,494 DOrville Apr. 30, 1918 1,495,620 Thomas May 27, 1924 1,651,971 Shield Dec. 6, 1927 2,669,248 Miller Feb. 16, 1954 FOREIGN PATENTS 440,786 France May 11, 1912 

